Study on corrosion behavior of high nitrogen steel welded joint assisted by ultrasonic vibration

Abstract

In this paper, the corrosion behavior of weld seam and HAZ in high nitrogen steel laser-arc hybrid welded joint was studied. By the assistance of ultrasonic vibration, the optimization effect of microscopic corrosion in different weld zone were compared. By electrochemical corrosion tests, it was found that the weak HAZ obtain greater performance improvement. The cavitation effect homogenized the corrosion traces of the weld seam in the form of dendrites refinement. And the ultrasonic vibration inhibited the extreme interfacial corrosion behavior at interface of HAZ and base metal. The welding pool crystallizes into finer grain structure and forms a stable moderating zone at the interface of heterogeneous metallography.